While research on the management and leadership of superintendents has been extensively conducted in the United States, empirical studies within the Japanese context remain limited. We analyzes the impact of municipal superintendents' turnover on student achievement using panel data from academic assessments conducted in an anonymous prefecture. We show that the effect of superintendents' turnover on academic performance varies across municipalities, exhibiting a roughly symmetric distribution around zero, with both positive and negative impacts. Furthermore, the impacts of superintendent turnover on scores in Japanese language and mathematics are positively correlated. These findings suggest that the management and leadership of municipal superintendents are among the key determinants of student achievement in Japan.